Semiconductor processing can be particularly sensitive to flow rate variations and perturbations. Thus, gas delivery systems for semiconductor processing chambers attempt to deliver steady flows at precise rates and pressures. Prior art gas delivery systems use flow-splitting methods to improve mix ratio accuracy, repeatability, and reproducibility in multi-injection point and multi-chamber architectures that share gas supplies. Flow splitting also reduces cost of the gas delivery system significantly in a number of applications. Flow splitting devices range from simple Y-piping to real time flow feedback ratio controllers (FRCs) which actively attempt to control the relative flow rates of gases dispensed via the FRC's output channels. However, as new technologies continue to achieve smaller critical dimensions, higher degrees of flow control precision are desirable. Thus, methods and apparatus are needed for enhancing gas flow rate control to be more precise.